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(No Model.) I 2 Sheets-Sheet 1. P. KUHMAIER.

ELECTRIC MOTOR.

No. 289,918. Patented Dec. 11, 1883.

n. PETERS, Fholo-mhognphur, Wnhmglun, n. c.

(No Model.) 2 Sheets-Sheet 2. F. KUHMAIER.

ELECTRIC MOTOR.

Patented Deo ll, 1883.

* Urvrran STATES PATENT @rrien.

FRANZ KI'THMAIER, or rnnssBURc, HUNGARY, assrcxon or ONE-HALF TO ALFREDSKENE, or KENNA, nusrnm.

ELECTRIC MOTOR.

SPECIFICATION forming part of Letters Patent No. 289,918, dated December11, 1883.

Application filed March 6, 1883.

To (07$ whom, it may concern.-

Be it known that I, FRANZ KUHMAIER, a subject of the King of Hungary,and a resident of the city of Pressburg, in the Kingdom of Hungary, haveinvented certain new and useful Improvements in Electromotors, of whichthe following is a specification.

In the accompanying drawings, Figure 1 is a side view, and Fig. 2 is afront View, of the electromotor. Fig. 3 shows amodification of thearrangement of the magnets. Figs. 4, 5, 6, '7, S, and 9 are detail viewson a larger scale.

In all the figures the same letters denote similar parts.

A are the fixed or field magnets, and B are the revolvingelectro-magnets. In all the fixed or field magnets A the polarities arekept constant, while in the revolving electro magnets the polarities arecontinuously changed by means of the commutator G.

D is a rheostat, by the downward movement of which gradually-increasedresistances may be thrown into circuit.

E is a governor connected with the rheostat, so as to throw greater orsmaller resistances into circuit, corresponding to the greater orsmaller rate of speed of the motor.

As may be seen in Figs. (5, 7, and 8, the commutator 0 consists of thedisk 0, secured to the standard 9 by the binding-screwy". The

front side of the disk 0 is, as shown in Fig. 7,

provided with insulated metal strips a and 3, connected at the back withthe conductingwires leading to the magnets whose north and south poles,respectively, are opposed to each other, as shown in Fig. 6. The brushesh and i are attached to the disks 7., secured to the revolving shaft j,with which they revolve. The brushes are connected to theconductingwires Z and m, which pass through the shaft j and lead to therevolved magnets 13.

It is obvious that when the commutator C, Fig. 7, is laterally moved asfar as the slot :0 permits the brush h will rest upon a strip, 8,instead of resting upon a strip, 92, and that the brush 1) will slidefrom a strip, 8, to a strip, 92. By thus shifting the commutator thecurrent fed by the conducting-wires o and 20 will be reversed, inconsequence of which areversal of polarity in the revolving magnets 13will take (X0 model.)

place, which magnets are connected with the commutator C by theconducting-wires Z and m. By this reversal of polarities the attractionand repulsion existing between the revolving magnets 13 and the fixed orfield magnets A will be reversed, and consequently the magnets B will berevolved in the opposite direction.

Figs. 4 and 5 show the arrangement for regulating the speed of the motorby means of a rheostat, D. The rheostat D is connected by the wire (Zwith the battery, and by the metal strip 16 it is connected with thefixed magnets A. The rheostat D consists, essentially, of the wire g,which is thick at the lower end and grows thinner toward the upper end.As well known, the resistance is greater the thinner the conducting-wireis. Consequently the more the rheostat D is lowered the greater theresistance offered by it to the electric current will be. Thus thecurrent passing through the motor will be the weakerthe lower therheostat D or the higher the strip t is placed. The raising of the stript is accomplished by the governor E. The greater the speed of the motoris the farther will the balls 1* r of the governor fiy asunder, and asthey are connected by the links 0 c to the strip 2, the latter will bepushed correspondingly higher when the rate 'of speed of the motor isgreat, and thus the current will be caused to pass through acorrespondingly longer and thinner wire. XVhen the rate of speed issmall, the balls 0 1- and the strip twill sink down, and a smallerresistance is then offered to the current. The direction in which thecurrent passes through the coils is in Fig. 9 indicated by arrows, inwhich figure a part of the whole ring of magnets is shown, and in whichthe coils and their connections are so arranged that the magnet-polesare alternately north and south.

It will be observed that the rheostat D is not alone automatic-that is,controlled by the governor E so as to regulate the speed of the motorbutthat it is also adjustable, so that the automatic control may beregulated, or brought within the limits of any given rate of speed whichit may be desired to obtain.

I claim- 1. The combination, with an electric motor,

2 seams of a rheostat, D, for regulating the rate of In testimon whereofI h I speed, said rheostat bein ca 3a 1 y a} e affixed my 31g- IOglafiual anal ?ut01matic adilstm enlaesgi natu1e 1n p1 esence of twowitnesses.

1a y as anc ort 1e pur )OSG described. T i 5 2. The combination 0% thegovernor E with FRAAZ KUHMAIDR' the mot able conductor t and rheostat D,for lVitnosses: controllingthe speed of an electromotor, said O. PAGETrheostat bemg capable of both automatic and E. G. KOELIiER manual adustment, substantially as described. I

It is hereby certified that in Letters Patent No. 289,918, grantedDecember 11, 1883, upon the application of Franz Kiihmaier, ofPressburg, Austria-Hungary, for an improvement in Electric Motors, theresidence of the assignee (Alfred Skene) of onehalf interest in saidinvention was written and printed Kenna, Austria, that it should havebeen written and printed Vienna, Austria and that the proper correctionhas been made in the files and records pertaining to the case in thePatent Office, and

should be read in the patent to make it conform thereto.

Signed, countersigned, and sealed this 18th day of December, A. D. 1883.

[SEAL] M. L. J OSLYN,

Acting Secretary of the Interior. Gountersigned:

BENJ. BUTTERWORTH,

Commissioner of Patents.

